Technical Field
The invention relates to an optical module, a display apparatus, and a method for driving the optical module. Particularly, the invention relates to a light source module, a display apparatus capable of switching a two-dimensional and a three-dimensional image mode, and a method for driving the light source module.
Related Art
In recent years, along with development of display techniques, amelioration of image dynamic effect, improvement of color performance and contrast, and people's pursuit for more realistic and richer viewing experiences, three-dimensional (3D) image displays have become one of actively developed products in related technical field. Generally, the 3D displays are grouped into stereoscopic displays and auto-stereoscopic displays. Related techniques of the auto-stereoscopic display are a field to be developed in related display industry in recent years.
The related techniques of the auto-stereoscopic display approximately include a holographic stereoscopic image display technique, a volumetric stereoscopic image display technique, a multi-planar stereoscopic image display technique and a multiplexed 2D stereoscopic image display technique, etc. according to working principles thereof. The multiplexed 2D stereoscopic image display technique has a function of switching 2D and 3D image display modes, and has a difference of lenticular lens and parallax barrier according to a beam splitting principle. The parallax barrier technique has been widely applied to various stereoscopic display products, and becomes a noticeable 3D image display technique in recent years.
Generally, main components of the 3D display using the parallax barrier technique include two liquid crystal panels and a microretarder disposed between the two liquid crystal panels, where the microretarder is an optical thin film having a specific pattern arrangement, which may produce different phase retardations for light passing there through. A basic principle of the parallax barrier technique is to implement switching of the 2D and 3D modes by using the phase retardation of the microretarder and using different polarizations of one of the two liquid crystal panels. When the display is in the 3D mode, a part of the light beam could be shielded. In this way, one eye of the viewer could only view odd pixel pairs of the 3D display, and another eye could only view even pixel pairs of the liquid crystal panel, so as to produce a stereoscopic image.
However, since light transmittances of the liquid crystal panel and the microretarder are not high, compared to a general display, the 3D display using the parallax barrier display technique has a poor light usage rate due to applying of the liquid crystal panel and the microretarder, on the other hand, the manufacturing cost thereof is increased. Moreover, since the 3D display using the parallax barrier display technique implements switching of the display modes by using different polarizations of the liquid crystal panels, a switching speed of the display modes is limited by a response speed of the liquid crystal panel, and fast switching cannot be implemented.
U.S. Patent Publication No. 20110242441A1 discloses a light guide plate having a strip diffusion area. U.S. Patent Publication No. 20120242931A1 discloses a display apparatus having a wedge-shaped light guide plate and a grid plate. Taiwan Patent No. 1262458, U.S. Pat. No. 7,364,343B2, China Patent Publication No. 102449509A, China Patent Publication No. 102483522A and U.S. Pat. No. 8,189,973B2 respectively disclose an optical system having a light guide plate of a wedge-shaped structure design.